How do you tell if you have a concussion?
Last updated September 3, 2026.
After a head hit, watch for headache or pressure, nausea, dizziness, blurry vision, light or noise sensitivity, fogginess, memory gaps, and feeling slowed down - and you do not need to be knocked out to have a concussion. Most involve no loss of consciousness, and some signs take hours to appear, so day one is for watching, not self-clearance. Emergency signs: worsening headache, repeated vomiting, slurred speech, growing confusion or drowsiness, unequal pupils, seizure, or inability to wake. Recovery is a day or two of physical and mental rest, then gradual return, and no sport until cleared - a second hit before healing is dangerous. Pymander is a free AI doctor, 24/7 by text, and can walk you through the checklist.
What to do
- Check yourself against the sign list: headache, nausea, dizziness, fogginess, memory gaps, sensitivity.
- Have someone watch you the first day: delayed signs are common.
- Know the emergency signs: worsening headache, repeated vomiting, slurred speech, unrousable.
- Stay out of sport until fully cleared: second-impact injuries are the dangerous ones.
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